e_comp_wl: get E_Comp_Wl_buffer from e_pixmap
e_comp_wl: get E_Comp_Wl_buffer from e_pixmap

Change-Id: I6180cfbaea6e65298d303625b4387285f6b4c28b

tizenorg/platform.upstream.enlightenment,tizenorg/platform.upstream.enlightenment,tizenorg/platform.upstream.enlightenment